Intelligent Optical Bypass Switch Implementation

Remote switches plate B passively monitoring optical power of the transmit fibers.Since the transceivers are continually transmitting Manchester-coded data or idle tone, this criterion is used in determining whether the switch should activate.When the optical signal is lost on a transmit fiber.It is determined that one of the following failure modes has occurred: either the LED has failed, the transceiver has lost power or been destroyed, or the building to -ring stub has been destroyed, or the building of a ring stub has been destroyed.In this event, the transceiver is automatically bypassed until repairs or replacement can be done.

A complete switch is composed of two identical channels.Each channel services one fiber of the dual counterrotating ring.At the coupling points, ,10 percent of the transmitted optical power are taped off and detected.A PIN photodiode with a low pass preamplifier is utilized to detect the average optical power incident on the detector.The detected power is amplified and compared to a threshold to be transformed into a logic high or low.The resulting digital value is used to place a latching optical switch reduces the abnormal electrical power requirements normally associate with the holding current in the traditional fails safe Mechanical Optical Switch  implementations.Additional circuitry gets power to the switch drivers and provides battery backup and recharge.

Prototype o two channel remote bypass switches were constructed.The prototype was placed in a simulated network environment to measure insertion losses, sensitivity, speed of response, and power consumption, In addition, operational test was carried out to examine switching response.Operation ofthe battery backup, and interoperability with the transceivers.

Operational tests showed the switch performed as designed.Switch transitions occurred at the preset threshold levels and within adequate time.Upon the loss of external power, the battery backup was noted to function correctly.
The laboratory prototype of the intelligent Optical Bypass Switch  was integrated into the survivable network testbed and produced the expected results.The use of this type of bypass switch in the final implementation can significantly enhance the probability of network survivability.


The laboratory prototype of the intelligent optical bypass switch was integrated into the survivable network testbed and produced the expected results.The use of this type of bypass switch in the ultimate implementation can significantly enhance the probability of network survivability.The MEMS Optical Switch design described above has been tailored for use in this application.However, the concept could be applied to other fiber optic ring architecture.In these applications, the switch would have to rely on the presence of the token or some other keep alive signal to determine the status of its.

Introduce To Opto-mechanical Switch

The Fiber Optical Switch can be a mechanical, opto-mechanical, or electronic device that opens or closes an optical circuit.The switch can be used for complete or break an optical path.Passive fiber optic switches will route an optical signal without electro-optical or optometrists conversion.However, a passive optical switch can use an electromechanical device to physically position the switch.An optical switch can get one or more input ports and two or more output ports.

As with any other type of switch, the MEMS Optical Switch has many uses, being dependent on the complexity of the design.In essence, the switch is the control for making, breaking, or modifying the connections within an optical circuit.This definition can be extended to incorporate the concept of the switch as the control that interconnects or transfers connections from one optical circuit to another.
It is important to note of the basic switch parameters for an optical switch.Some of the performance parameters to consider are the number of input and output ports(required size of the switch) ,optical fiber type,connector type,center wavelength,bandwidth,losses,crosstalk,switching speed ,durability (number of switching cycles),power handing ,and repeatability (the amount of change in output power each time the switch changes stage).

An Opto-mechanical Switch  redirects an optical signal by moving fiber or  bulk optic elements by means of mechanical devices.These types of switches are normally stepper motor driven.The stepper will move a mirror that guides the light from the input to the desired output.Although photomechanical switches are inherently slow due to the actual physical movement of the optical elements, their reliability, moderate insertion losses, and minimal crosstalk make them a widely deployed type of switch.


The opto-mechanical switch works on the premise that the input and output light beams are collated and "matched" within the switching device--the beams are moved within the device to make sure the switched connection from the input to the output.The opto-mechanical switch can be physically larger than alternative switches.But many micromechanical fiber-optic switches are available.

Introduce To Mechanical Optical Switch

The development of practical optical switches will probably be the final step in the deployment of the complete optical network of the next decade switching has always bottleneck that has yielded many innovative solutions and novel implementations ,so there should be an array of switching techniques developed as designs shift toward the Mechanical Optical Switch .We have defined a whole new set of signals that not only need to be multiplexed and demilitarised, but is required to provide the vast switching matrix required for efficient communications.Optical switches and cross connects will take the place of today's intermediate devices, maintaining the functionality of current switches, routers, and gateways.

Several optical fiber switches are generally used for telecommunicatoins using an optical network.Mechanical 1*2 optical switches which adjust the optical axis of fibers by mechanical motion of a movable fiber have been developed using several micro actuator.Including SMA actuators.The switches have advantages of low insertion loss and high cross -channel isolation because of the admirable optical property of optical fibers.

Utilizing standard optical fibers, mechanical 1*2 optical switches have been fabricated.A meandering SMA actuator for lateral displacement of a movable fiber has been fabricated by laser cutting of an SMA sheet.V-grooves for precise positioning of the movable fiber are fabricated by anisotropic etching of the Si substrate.

Mechanical 1*2 optical switches using Plastic Optical Fiber Cable (POF) with a relatively large core diameter have been developed.A magnetic latch keeps the position of the movable POF on the left or right side at a steady state.SMA microcode is included with a magnetic material ring and electrodes by soldering.

The evolution of optical communications systems indicates that the optical networks of the near future will be mesh-based WDM nodes with multilaterally switching capabilities.This innovative optical transport layer will use optical cross connects and Roadms,. To establish fast reconfiguration and provisioning of bandwidth for the transport of all types of communications protocols, since a constant Mechanical Optical Switch is not yet available, MEMS Optical Switch  is currently utilized.